Range View of Nuclear Energy

IT MAY be startling to realize that only about 3 per cent of the U.S. national income is spent to furnish the energy we use. From this, it is evident that no golden age can be created by reducing this expenditure —not even by reducing it to nothing. 

On the other hand, a substantial increase in the efiEort now necessary to provide our energy requirements might be a serious calamity. Thus, the true objective of reactor research may well be the preservation of our present iron age. This point underlies the following discussion of whether reactor research ought to have as its primary aim the development of liumers or of Tireedeis.  

Natural uranium contains only 0.7 per cent of the fissionable isotope U-235. In burners (burner reactors) only this 0.7 per cent of the total energy content of the uranium is utilized, and even this fraction cannot be utilized completely. Converter reactors are somewhat more efficient in their present-day embodiments, they produce enough plutonium to permit, in principle, the doubling of the energy content of the U-235. 

Breeder reactors, on the other hand, can convert virtually all of U-238 into fissionable plutonium, producing about 140 times more energy than burners, and 70 times more than low-conversion ratio reactors. 

The breeder vs. burner argument, therfore, revolves around the question How necessary is it to utilize the bulk of the energy content of uranium and thorium, and to what extent can we be satisfied with the utiliza-tioh of a small fraction of this energy content. Through- 

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Wigner, E. P. and Weinberg, A.M., Longer Range View of Nuclear Energy , Bulletin of the Atomic Scientists 16, 10, 1960. 

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